Precision Shaft Alignment for Centrifugal Compressors

Alignment should be verified after any maintenance activity that disturbs the centrifugal compressors mounting position, after foundation repairs, and whenever vibration data suggests misalignment. Annual verification checks are recommended for critical equipment even without maintenance activities, since thermal growth, pipe strain, and foundation settling can shift alignment over time.

Alignment tolerances for centrifugal compressors are typically set by the coupling manufacturer or equipment OEM and vary with operating speed. Higher-speed equipment requires tighter tolerances. Laser alignment systems measure to 0.001 mm resolution, achieving repeatability well within the tolerances specified by API 617 and coupling manufacturers.

Baseline is alignment on install and after any disturbance. Adjust based on duty cycle: assets running near rated capacity 24/7 get tighter intervals; intermittent-duty units can stretch the interval by 50 percent. The general rule for Centrifugal Compressors specifically is that PdM cadence should be no more than half the dominant failure mode's P-F interval. For most Centrifugal Compressors populations that lands at continuous API 670 monitoring on critical units.

The Centrifugal Compressors failure population is dominated by thrust bearing wear, seal degradation, rotor fouling. Each leaves a different signature: rising axial position, shaft vibration drift. Precision Shaft Alignment captures these via angular and offset misalignment to OEM spec and trends them over the alignment on install and after any disturbance schedule. Early-stage indicators appear before functional failure — the lead time runs immediate (event-driven) on most modes.